The UK government is expected to make a significant announcement on reducing its emissions to help tackle climate change, Sky News understands.
Preparations are being made to set a new target in law to reduce emissions - it's thought by 78% by 2035 compared to 1990 levels.
That would be in line with recommendations by the Committee on Climate Change, which advises the government how to get to net zero.
Crucially, any new pledge could include emissions from aviation and shipping for the first time.
It would mean an increase in ambition on the international pledge made by the UK government last December to reduce emissions by 68% by 2030.
An announcement is expected in the week the US prepares to host a virtual summit of world leaders aimed at driving forward global ambition on the climate, giving Boris Johnson something to bring to the international table.
The US is expected to lay out its own emissions cuts at the event.
And it would boost the UK's credibility ahead of hosting the major COP26 climate summit in Glasgow in November.
The UK can't afford to make its move too late with big polluting nations like China - under pressure to up its ambition - watching carefully.
However, the government is under pressure to back up any new target with policies and investment and put the foundations in place to reach net zero.
Ed Matthew, campaigns director for the climate change think tank E3G, said: "Setting an ambitious emission reduction target would boost the UK's diplomatic drive to persuade other countries to set out ambitious targets of their own.
"That is one of the big tests of UK climate diplomacy ahead of the COP26 climate summit.
"The UK now has the opportunity to spark a global green industrial revolution but ultimately its credibility will rest on action. It must now put in place the policies and investment needed to achieve the target.
"That is the mark of true climate leadership."
The UK was one of the first major economies to commit to reaching net zero.
The improved emissions pledge would be an ambitious undertaking, but hitting the target is easier said than done.
Chris Venables, head of politics at the think tank Green Alliance, said: "Without bold and urgent action in this parliament, the UK's climate targets could slip out of reach.
"There's a significant gap between what the government says it would like to do on climate versus what is happening on the ground - targets like this one make it even more important they match ambition with reality."
The world is not currently on track to reduce its emissions enough to keep global warming within the goals laid out in the 2015 Paris Agreement of 1.5C above pre-industrial levels and well below 2C.
But global emissions are still going up. A cut in emissions of 45% globally is needed in the next 10 years.
Sky News broadcasts the first daily prime time news show dedicated to climate change.
Hosted by Anna Jones, The Daily Climate Show is following Sky News correspondents as they investigate how global warming is changing our landscape and how we all live our lives.
The show will also highlight solutions to the crisis and show how small changes can make a big difference.